Measurement and analysis of vibrations - Evaluation of the criteria of acceptance ISO Standard 10816-6

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Measurement and analysis of vibrations - Evaluation of the criteria of acceptance ISO Standard 10816-6
Measurement and analysis of vibrations - Evaluation
      of the criteria of acceptance ISO Standard 10816-6
         Medición y análisis de vibraciones – Evaluación del criterio de aceptación Norma ISO 10816-6.

DOI: https://doi.org/10.25043/19098642.196                                                                 Roger Arévalo Gómez 1

                                                            Abstract
During the reception and / or delivery tests of a ship, vibration measurement and analysis is made to
the propulsion line in order to evaluate and predict the condition of the machinery. The values taken
during the measurement of the vibrations are evaluated with the acceptance criteria provided by the
standards. International Standard ISO 10816-6 (1995) focuses on reciprocating machinery with power
of greater than 100kW, is used by both analysts and manufacturers of propulsion machinery for ships.
Through this work, we intend to evaluate the acceptance criteria of this norm in boats smaller than
100 meters. At the end of this work it is concluded that the standard must be updated, indicating
and differentiating the acceptance criteria for machinery taking into account its type of anchorage to
the structure (flexible or rigid), boats with length less than or greater than 100 meters and the Ship
building material (Aluminum, Steel or Composite material).

Key words: Reciprocant, Vibration level.

                                                           Resumen
Durante las pruebas de recepción y/o entrega de un buque se realiza medición y análisis de vibración a
la línea de propulsión con el fin evaluar y predecir la condición de la maquinaria. Los valores tomados
durante la medición de las vibraciones son evaluados con los criterios de aceptación que entregan las
normas. La norma Internacional ISO 10816-6 (1995) se enfoca en la maquinaria reciprocante con
potencia de rateo mayor a 100kW, es utilizada tanto por analistas como por fabricantes de maquinaria
propulsiva para buques. Por medio de este trabajo se pretende evaluar los criterios de aceptación de esta
norma en embarcaciones menores a 100 metros. Al final de este trabajo se concluye que la norma debe ser
actualizada, indicando y diferenciando los criterios de aceptación para maquinaria teniendo en cuenta su
tipo de anclaje a la estructura (flexible o rígida), embarcaciones con eslora inferior o superior a 100 metros
y el material de construcción del buque (Aluminio, Acero o Material compuesto).

Palabras claves: Reciprocante, nivel de vibración.

Date Received: January 17th 2019 - Fecha de recepción: Enero 17 de 2019
Date Accepted: March 3rd 2019 - Fecha de aceptación: Marzo 3 de 2019

1
    COTECMAR. Cartagena, Colombia. Email: rarevalo@cotecmar.com

                                        Ship Science & Technology - Vol. 13 - n.° 26 - (39-44) January 2020 - Cartagena (Colombia)   39
Roger Arévalo Gómez

Introduction                                                           Therefore, it was determined to reclassify
                                                                       the machinery at least to level 3 indicated by
ISO 10816-6 "Mechanical vibration - Evaluation                         the standard. By doing this, we had a more
of machine vibration by measurements on non-                           accurate alarm of the novelties presented by the
rotating parts - Part 6: Reciprocating machines                        diesel machinery and determined through the
with power ratings above 100 kW", specifies                            measurement and analysis of linear vibrations.
the conditions and general procedures for the
measurement and evaluation of the linear
vibrations, in measurements made on the non-                           Presentation of the problem
rotating parts of reciprocating machines with
powers greater than 100 kW.                                            Before COTECMAR, had the ability to meet the
                                                                       service of measurement and analysis of vibrations
Typical examples of application are marine                             lines with its own strength, this was executed by
propulsion engines, Diesel engine generator sets,                      means of contractors, local companies specialized in
gas compressors and diesel engines for locomotives.                    measurement and analysis of vibrations, but who did
This standard does not apply to machines installed                     not have the knowledge in the area ship, the behavior of
on road vehicles.                                                      the marine combustion machinery and the standards
                                                                       used by these companies were not adequate.
ISO 10816-6 in Annex A "Classification of
vibration in machinery" indicates a qualification                      The ignorance in the behavior in marine diesel
of reciprocating machinery. In said classification,                    machinery and the lack of use of an adequate
the standard establishes that diesel and industrial                    norm in multiple occasions caused complaints and
marine engines can be classified either 5, 6 or 7.                     complaints on the part of the final client due to a
                                                                       bad concept or conclusion on the part of the analyst.
Since 2013, COTECMAR has acquired the
technological and human capacity to carry out                          By training personnel in the naval area, certifying
with its own force the measurement and analysis                        it in vibration analysis under the guidelines of ISO
of the linear vibrations of the ships belonging                        18436-2 in level II and acquiring equipment for
to the Colombian Republic Navy (ARC) and                               the measurement and subsequent analysis of the
private customers.                                                     linear vibration measurement, gave COTECMAR
                                                                       a better answer. customers, reducing the number
In these more than four years the experience in the                    of complaints and claims, which was seen in a
measurement and analysis of linear vibrations in                       significant increase in the number of services that
the propulsion lines of ships has been strengthened,                   went from 9 in 2014, 42 in 2015, 46 in 2016, 40 in
which includes an internal combustion engine,                          2017 and 46 services in 2018.
a power transmission box and revolutions to the
transmission shaft and finally to the propeller.                       For the analysis of measured vibrations, the criteria
                                                                       of ISO 18816 and its six different parts are taken as
In more than 63 ships served in this period (2013                      acceptance criteria:
to 2018) measurements and analysis of linear
vibrations were made to diesel engines of ARC and                      •     Part 1: General guidelines.
private vessels, totaling approximately 150 services.                  •     Part 2: Large steam turbine generator sets on
At the beginning there were many inconveniences                              land exceeding 50 MW.
and complaints from the client because although                        •     Part 3: Industrial machines with nominal
the global vibrations did not reach the minimum                              power greater than 15 kW and rated speeds
level, level 5, required by ISO 10816-6 to consider                          between 120 r / min and 15 000 r / min when
an alarm in the diesel machinery, in reality, there                          measured in situ.
were developments in the engines, which affected                        •     Part 4: Sets powered by gas turbines, excluding
the credibility of the client.                                               aircraft derivatives

  40     Ship Science & Technology - Vol. 13 - n.° 26 - (39-44) January 2020 - Cartagena (Colombia)
Measurement and analysis of vibrations - Evaluation of the criteria of acceptance Norma ISO 10816-6

•   Part 5: Sets of machines in hydraulic generating          The values of the vibration measurements were
    and pumping plants.                                       taken in the diesel combustion engines according
•   Part 6: Reciprocal machines with nominal                  to ISO 10816-6 [1].
    powers greater than 100 kW.
                                                                                  Fig. 1. Diesel engine in L.
In order to evaluate the vibrations measured
in the propulsion lines of the ships, ISO 10816-
3[2] standards are adopted for gearboxes, support
points and bearings and ISO 10816-6 [1] for the
evaluation of propulsion engines.

The norm ISO 10816-3 [2] establishes criteria
for the levels of the linear vibrations measured
according to the power, revolutions per minute of
rotation and type of support or anchoring of the
equipment (flexible, rigid or semi-rigid).

The norm ISO 10816-6[1] classifies the vibration of
the machinery in seven levels. The standard does not
indicate how to classify the machinery that is being
measured. It only indicates that as an example many
industrial and marine Diesel engines are classified
5, 6 and 7. But it does not give more details.
Manufacturers of marine engines such as Wartsilla
and MTU give a rating of 5 to their engines.
                                                                         Fig. 2. Multi-cylinder Diesel engine in V.

Measured Data
                                                                                        1
Between 2013 and 2018, more than 150 diesel
combustion engines from different manufacturers
and models have been vibrated. The following is
a summary of the brands and models of diesel
combustion engines serviced.

    Table 1. Summary of Brand and Model of Diesel                                                               2
                 Engines serviced.

                  BRAND - MODEL
        MTU - 12V M70
        MTU - 1163 TB93
        CATERPILLAR - 3412
        CATERPILLAR - 3056
                                                              Points 1 and 2 are called free side and side coupling
        CATERPILLAR - C18
                                                              respectively. At each point the measurement is made
        DETROIT DIESEL - 6L 2T
                                                              in the three directions Vertical (V), Horizontal
        DETROIT DIESEL - 6L 71T
                                                              (H) and Axial (A).
        DETROIT DIESEL - 16-645 E2
        MAN B&W - 6L23/30A                                    The data taken is compared with the classifications
        CUMMINS                                               and acceptable levels given in ISO 10816-6 [1].

                                Ship Science & Technology - Vol. 13 - n.° 26 - (39-44) January 2020 - Cartagena (Colombia)   41
Roger Arévalo Gómez

                                                                  Fig. 3. Comparison of global vibration values with the acceptance criteria according to ISO 10816-6.
MEDICIONES GLOBALES DE VIBRACIÓN EN RMS (mm/s)

                                                   80,00                                                                                                                                                                         1-H
                                                                                                                                                                                                                                 1-A

                                                   70,00                                                                                                                                                                         1-A
                                                                                                                                                                                                                                 2-H
                                                                                                                                                                                                                                 2-V
                                                   60,00
                                                                                                                                                                                                                                 2-A
                                                                                                                                                                                                                                 Clasificacion 1
                                                   50,00                                                                                                                                                                         Clasificacion 2
                                                                                                                                                                                                                                 Clasificacion 3
                                                   40,00                                                                                                                                                                         Clasificacion 4
                                                                                                                                                                                                                                 Clasificacion 5

                                                   30,00                                                                                                                                                                         Clasificacion 6
                                                                                                                                                                                                                                 Clasificacion 7

                                                   20,00

                                                   10,00

                                                    0,00
                                                        300       400   500   600   700    800   900   1000   1100    1200   1300   1400   1500   1600   1700   1800   1900   2000   2100   2200   2300   2400   2500   2600    2700    2800

                                                                                                                                             RPM

                                                                  Fig. 4. Comparison - Values Of Global Vibration Vs Classification Levels - Motors Without Failure.

                                                      80,00
  MEDICIONES GLOBALES DE VIBRACIÓN EN RMS (mm/s)

                                                                                                                                                                                                                          1-H
                                                      70,00                                                                                                                                                               1-A
                                                                                                                                                                                                                          1-A
                                                                                                                                                                                                                          2-H
                                                      60,00
                                                                                                                                                                                                                          2-V
                                                                                                                                                                                                                          2-A
                                                      50,00                                                                                                                                                               Clasificacion 1
                                                                                                                                                                                                                          Clasificacion 2
                                                                                                                                                                                                                          Clasificacion 3
                                                      40,00
                                                                                                                                                                                                                          Clasificacion 4
                                                                                                                                                                                                                          Clasificacion 5
                                                      30,00                                                                                                                                                               Clasificacion 6
                                                                                                                                                                                                                          Clasificacion 7

                                                      20,00

                                                      10,00

                                                           0,00
                                                                  300   400     500       600    700   800      900     1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000 2100

                                                                                                                                             RPM

           For the analysis, 23 vessels were taken into                                                                                           misalignments of engine parts, such as high levels
           account, each of which possesses two propulsion                                                                                        of cooling water temperature or low oil pressure,
           lines, so in total 46 engines were examined. As                                                                                        associated with a lack of maintenance.
           shown in illustration 6, of the 48% of the ships
           to which the global vibration measurements were                                                                                        If marine diesel engines continue to be evaluated
           taken, their engines present failure even with                                                                                         under ISO 10816-6[1] in the considerations
           vibration magnitudes below the classification 5                                                                                        that this indicates, failures could arise due to an
           indicated in ISO 10816-6 [1]. These failures are                                                                                       erroneous decision, for example a propulsion
           related to sources other than poor installation or                                                                                     engine could be presented with vibration levels

                                                   42         Ship Science & Technology - Vol. 13 - n.° 26 - (39-44) January 2020 - Cartagena (Colombia)
Measurement and analysis of vibrations - Evaluation of the criteria of acceptance Norma ISO 10816-6

                                                                     Fig. 5. Comparison - Global Vibration Values Vs Classification Levels - Faulty Engines.

                                                   80,00
MEDICIONES GLOBALES DE VIBRACIÓN EN RMS (mm/s)

                                                   70,00
                                                                                                                                                                                         1-H
                                                                                                                                                                                         1-A
                                                   60,00
                                                                                                                                                                                         1-A
                                                                                                                                                                                         2-H
                                                   50,00                                                                                                                                 2-V
                                                                                                                                                                                         2-A
                                                                                                                                                                                         Clasificacion 1
                                                   40,00
                                                                                                                                                                                         Clasificacion 2
                                                                                                                                                                                         Clasificacion 3
                                                   30,00                                                                                                                                 Clasificacion 4
                                                                                                                                                                                         Clasificacion 5

                                                   20,00                                                                                                                                 Clasificacion 6
                                                                                                                                                                                         Clasificacion 7

                                                   10,00

                                                    0,00
                                                           300 400 500 600 700 800 900 1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000 2100 2200 2300 2400 2500 2600 2700

                                                                                                                        RPM

                                                    Fig. 6. Comparison - Global Vibration Values Vs Classification Levels - Faulty Engines with Values below the
                                                                                                  Qualification 5.

                                                  80,00
 MEDICIONES GLOBALES DE VIBRACIÓN EN RMS (mm/s)

                                                                                                                                                                                            1-H
                                                  70,00                                                                                                                                     1-A
                                                                                                                                                                                            1-A

                                                  60,00                                                                                                                                     2-H
                                                                                                                                                                                            2-V
                                                                                                                                                                                            2-A
                                                  50,00                                                                                                                                     Clasificacion 1
                                                                                                                                                                                            Clasificacion 2

                                                  40,00                                                                                                                                     Clasificacion 3
                                                                                                                                                                                            Clasificacion 4
                                                                                                                                                                                            Clasificacion 5
                                                  30,00                                                                                                                                     Clasificacion 6
                                                                                                                                                                                            Clasificacion 7
                                                  20,00

                                                  10,00

                                                   0,00
                                                      300      400    500    600    700    800      900   1000   1100    1200    1300   1400   1500   1600   1700   1800   1900   2000    2100
                                                                                                                         RPM

 above the classification 4 that was affecting the                                                                               Conclusion
 structural integrity of the vessel. Or have a diesel
 combustion engine whose levels of vibration were                                                                               There are engine failures, even if these have global
 above classification 5 but that did not present                                                                                vibration levels below the minimum classification
 problems of mechanics, simply the base where it is                                                                             suggested by ISO 10816-6[1], so the classification
 supported is flexible and the material of the vessel                                                                           indicated by ISO 10816-6[1] should be modified,
 is made of aluminum or composite material.                                                                                     the standard should have the ability to indicate, as is

                                                                                           Ship Science & Technology - Vol. 13 - n.° 26 - (39-44) January 2020 - Cartagena (Colombia)              43
Roger Arévalo Gómez

the norm ISO 10816-3[2], the levels of acceptance                            (Temperature, Pressure) exceed the alarm
according to their power, the type of anchoring of                           value. This is because for the vibration levels
the engines, whether rigid or flexible and also the                          to be considered high or harmful, it is because
construction material of the vessel.                                         the machinery is suffering some affectation
                                                                             reflected in its temperature and operating
The way of obtaining the accepted levels of                                  pressure of Oil, Fuel, Cooling Water.
vibration for marine diesel engines could be in two
ways:                                                                  With these values of vibration lines would be
                                                                       created more real acceptance levels and would
•    Establish a list of the linear vibration levels in                help to make a more assertive diagnosis to diesel
     Diesel internal combustion engines installed                      propulsion engines.
     in new vessels, tabulating power, number of
     banks (1 or 2), propulsion line numbers, type
     of anchoring of the bases (Flexible, Rigid or                     References
     Semi-rigid) ) and material of the vessel (Steel,
     Aluminum or Composite Materials) and create                       1. ISO. (15 de Diciembre de 1995). ISO 10816-6.
     a tendency to depart from said primary values                        Mechanical vibration -- Evaluation of machine
     by handling a first alarm (Caution) of 25% of                        vibration by measurements on non-rotating
     the initial value.                                                   parts -- Part 6: Reciprocating machines with
                                                                          power ratings above 100 Kw.
•    Set up a list of linear vibration levels in diesel                2. ISO. (15 de Mayo de 1998). ISO 10816-
     internal combustion engines after maintenance                        3. Mechanical vibration — Evaluation of
     tabulating power, number of benches (1 or 2),                        machine vibration by measurements on non-
     propulsion line numbers, type of anchoring                           rotating parts — Part 3: Industrial machines
     of the bases (Flexible, Rigid or Semi-rigid)                         with nominal power above 15 kW and nominal
     and material of the vessel (Steel, Aluminum                          speeds between 120 r/min and 15 000 r/min
     or Composite Materials) and register the                             when measured in situ.
     vibration values when the operating parameters

    44   Ship Science & Technology - Vol. 13 - n.° 26 - (39-44) January 2020 - Cartagena (Colombia)
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